(,Branch <br />ENfGIN EERIN G= <br />Since 1977 <br />September 21, 2o16 <br />Rick Satre <br />Schirmer Satre Group <br />375 W 4th Ave #201 <br />Eugene, OR 97401 <br />RE: METRO PLAN ALIGNMENT <br />LAURELRIDGE ZONE CHANGE (Z 15-5) <br />Branch Engineering Inc. Project No. i1-o68:2d <br />Dear Rick, <br />Enclosed is a cd with an AutoCAD drawing suitable for developing a relationship between <br />the site and the "Eugene-Springfield Metropolitan Area General Plan Diagram". To create this <br />drawing, boundary lines away from the site were calculated and incorporated into our previous <br />survey work. <br />Prior to calculating the new data, I needed to establish accuracy tolerances. In situations <br />like this, engineering and surveying tolerances are often determined on the principle of the answer <br />only being as accurate as the least accurate measurement. During the meeting on March 30t', you <br />provided us with a plotted drawing titled "Zone Change: Metro Plan Diagram on Subject Prop." <br />sheet ZC-4, and subtitled "Exhibit L Adopted 2004 Metro Plan Map: Rotated", revision date 9-2- <br />15. Since the new data is for refining this drawing, I based my accuracy tolerances on it. The <br />Metro Plan Map used as a background in this drawing has visible pixilation, with each pixel scaling <br />at 15 feet. The lines and boundaries between colors are all several pixels across. This means that <br />a survey line has a range of about 45 feet (aka 22.5 feet) where it could fall and still be <br />considered as aligning with the Metro Plan Map as shown on this drawing. By standard <br />engineering and surveying principles, I could adopt 22.5 feet as an acceptable tolerance. <br />However, since this work will be reviewed by a variety of non-technical people who may not <br />understand this as being an acceptable tolerance, I elected to set a tolerance of a 1/2 pixel (7.5 feet <br />or 3.75 feet). <br />The following is a discussion of the accuracy for each calculation. <br />3oth Avenue, centerline <br />The centerline of 3oth Ave was calculated using centerline monuments set by the County <br />Surveyor during the slide repair project in 1997. The monuments were recovered in good <br />condition and matched the survey data shown on the survey. The accuracy of the road centerline <br />location is better than can be measured with our survey equipment, being less than o.o1 feet. <br />EUGENE-SPRINGFIELD SALEM-KEIZER <br />310 51h Street, Springfield, OR 97477 1 p: 541.746.0637 1 f: 541.746.0389 1 www.branchengineering.com <br />